EXP11's deliver brilliant, crisp acoustic tone and last 3 to 4 times longer. The ultimate extended life strings!

EXP Coated 80/20 Bronze Acoustic Guitar Strings are D’Addario’s brightest sounding coated strings and provide longer life and increased durability. Here is how it works: An ultra-fine layer of EXP Coating is bonded to the 80/20 bronze wrap wire, which is then wound onto the hex-shaped core wire. The result is a built-in barrier against the corrosion and wear that can quickly sap the life out of your strings and your sound. And since the EXP Coating is cross-linked to the wrap wire prior to winding, the strings retain their natural round wound feel, and keep their "new string tone" three to four times longer than traditional guitar strings.

I have been playing acoustic guitar for over a decade and these are the only strings I will put on my guitars. I have tried several others but always go back to the D'Addario EXP11. Great sound and excellent product.